Process of concentrating ores



BENJAMIN E. DOSENBACH, OF BUTTE, MONTANA; EDNA MLJOSENBACH EXECUTRIX 0F SAID BENJAMIN E. DOSENBACH, DECEASED.

PROCESS CONCENTRATING GRES.

Applicationmed December Y. following is a specification.

My invention consists' in means .for concentrating ores by a combina-tion of the leaching and flotation methods.

In some instances copper ores conta-in sulphide copper, together withrthe various oxides, carbonatos, silicates, etc. of copper.

My process isadapted to the treatment of ores of this class. The'sulphide copper in" such ores remains practically unaltered during the leaching operation by which the oxides, carbonatos and silicates of copper are dissolved, and after the dissolved copper.

is'. precipitated the application of the flota.-

tion step results iu floating,r the sulphide copper, together with the precipitated metallic copper. l f

Briefl stated, my `process consists, first, in grin ingJ the ore as finely as ymay be necessary to eflect the most rapid and complete solution of the copper oxide, carbonate and silicate, the existence of slimcs in the 'ore` pulp being no disadvantage inthe applica Y .tion of the subsequent sbep of the process.

A After the sulphuric which is added to 'the pulp, has dissolved the copper, I precipitate the copper, in metallic forni, preferably by the use of irouscrap. U p to this point no sep-arationol the metallic copper or sulphide from the remainder o tli'eore in the pulp has been ell'wted. The copper has simply been dissolved, forming the sulphateyand then precipitated as metal, the process up to this point consisting,r simply 1n transforming the copper oxides, carbonates, silicates, etc. into metallic copper. Having effected this conversion of the copper intoa free metal, I have found that the metallic copper and the sulphides can be simultaneousl separated by the ordinary tlotation1net ods.v At this point, therefore, I introduce air into the pulp, either by agitation orvby passing the air-'through soinsl porous medium, whereupon the me-` tullio copper tloats as ajroth and is floated from the surface of the pulp-in the methods vordinarily used in flotation operations.

White the vair introducedcinto' the pulp by 7, 1915. seran Nb. 65,435.

agitation, or by other means, is the principal instrumentality for separating and floating the copper, it may be that gases, such as hydrogen, carbon dioxide, and hydrocarbons are formed. hydrocarbon gases I have found to be quite noticeable, resulting probably from moreA or less complicated actions taking place between the sulphuric acid, the iron, thel carbon and sulphur contained in the iron, the copce per minerals contained in the ore, and in,- ter-actions between the various products formed. Whatever fthe precise chemical reactions may be the generation of such hydrocarbon gases is frequently very notice- 7e able.

'lt will be obvious that many varieties of mechanism may. be employed in the application of myprocess. As an example of a suitable arrangement of apparatus, l have 75 villustrated in the drawing formingv part of this application an arrangement similar .to that used by me.. The drawing is diagrarnmatic, takingin fthe form of what is generally termed a dow sheet. tion and explanationof the apparatus used is `unnecessary for the reason that all of the apparatus is of a type old and well known in the" art. l

i Referring to the drawing:

The ore suitably crushed, say to a maximum size of about one-fourth of an inch, is suppliedto the apparatus from a binV A. The sulphuric acid used forleacliing may be supplied from a tank B. The ore and 90` jsulphuric acid, together Ywith sufficient water to makea pulp, of proper consistency, are conducted to a tube mill Cfwhere the ore is simultaneously subjected to as,

fine grinding as necessary, an to thesol-f 95 lvent action of the sulphur-ic acid. Ordinarily the copper oxides, carbonates, andsilicates will enter completely into solution in the pulpiwhile in the tube Inill referred to, but,' of course, if a enger interval of 100 time is necessary to eiteot the solution of the Copper than is necessary for the grinding ofthe ore, the acid may be given further time foracting, by conducting the pulp fromv thetube mill to somesuitable vessel 105 for that purpose. Ordinarily,` however, after the ore. has been ground in the tube mill in the presence of the added sulphuric acid, the copper-will be completely 'dissolved andtheppulppmaythen be conducted to a 1ro The generation of 6G Detailed illustraso horizontal rotating cylinder D, which conthe rotating cylinder D, is firstc'onducted to a Dorr tank, or other Settling device,.f'or subsequent treatment. At present, however, l will describe the method of operation utilized when the pulp is conducted directly from the tube mill C to the rotating cylinder D. In this case the rotationof the cyl inder D causes efficient Contact between the scrap iron therein contained and the pulp which passes through the cylinder D from left to' right, as shown in the drawing. The rotation of the cylinder D 'further has the effect of freeing the surface of the scrap iron .from the precipitated copper, and b suitably timing rthe flow of' pulp througi the cylinder D, all of' the dissolved copper may be precipitated therein. The prec1pitated cop er, however, is not retained in the cylinder ID, but, being precipitated in the L:ai

ment copper and sulphide, as distinguishedv from the carbonaies, silicates, and oxides, in which the copper. originally existed. 85 The object of the operation soffar described is simply to effect the conversion of the copper carbonates, silicates andoxides into themetallic form.

AThe pulp discharged from the rotating cylinder D contains the copper in the ineytallic forni and inthe form ot sulphide, and in :these forms it is arnenable to flotation treatment, which may be effectedr in any of the well known forms of' apparatus, such, for

is introduced into the pulp under sufficient pressure `through a porous `Wall or byy vmeans of jets. 'Such ineans of effecting pulp, 'is carried with the pulp and the prodinstance, Aasrthat illustrated 'in latent'No.

srabovc stated,`tlic flotation mayv be effected in apparatus in which the airl flotation are illustrated in' Patent No. 793,- d

808,'granted to H. L. Salman and H. F. Kirlqiatrick-Picard, July 4:, 1905, and lPat-I ent No. 1,104,735, granted to J. M. Callow 5. July 2l, 1914. vThe flotation operation, hovveuer comlucted, and whatever apparatus used, results'in the vflotation of the ecment copper, together with" the sulphide copper contained in the ore, inthe form of' a froth, which nia-y be floated' of from the remainder of the pulp and separated in the way ordinarily practiced in flotation operations. As above stated, I have in some instances found the addition of a frothing agent, such as an oil, or otherof the substances hercinbcforc enumerated, un necessary, but my process'is not restricted to the use, or nonuse, or the use yof any particulaigfloating agent, and includes the op` erationregardless of Whether the, flotation be effected by the addition of frothing agerits', or by the properties imparted to the pulp ,by the various salts formed in the leaching operation. J

What I claim is l. A process of concentrating orcs coml. t prising the operations of reducing theore to a wet pulp adding acid. thereto'fn dis# solve the metal, settling the pulp containing the dissolved metal, overflowing the clear liquor, yprecipitating the metal from the .clearliqumg then precipitating the dissolved metal in the vthickened pulp, and separating the precipitated metal from the remainder of the thickened pulp by flotation. y

2. 'A process of concentrating ores comprising the operations of reducing the ore to al wet pulp, adding acid thereto to dissolve the-metal, settling the lpulp contain# ing the dissolved metal, overflowing the "clear liquor, precipitating the metal from i the clear liquor, adding the clear liquor from which the metal has been so separated to the leaching solution, then precipitating y the' dissolved metal in Athe thickened pulp-,' and separating the precipitated metalfrom' the remainder of the thickened pulp by flotation;

In test-imonyfwhereof, have subscribed my name.v 1

- BENJAMIN H. nosENBACH. L

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